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Mechanical features : Types of construction : Standard motors are designed for foot mounting (B3). These are also suitable for B6, B7, B8, V5, V6 mounting without any change. Motors can be supplied in flange mounting (B5). These motors will also be suitable for V1 & V3 mounting without any change. The flame proof motors manufactured by BBL are suitable for ignition groups G1 to G4 as per VDE 0170/0171or Temperature Class T1 to T4 as per IS 6381. Main Characteristics Sturdy housing which prevents an internal explosion from spreading to the outside and resists the explosion pressure. Robust bearing shields and caps bolted to the frame in such a manner that the gaps remain unaffected in the event of an internal explosion. Screen on air intake with a mesh size not exceeding 8 mm External earth terminals Protective earth conductor terminal in the terminal box. Ex (d) mark on the motor. CMRI certificate No., CCE & DGFASLI certificate No. & ISI Licence mark on the name plate. Special varnishing and painting treatment to resist highly corrosive atmosphere. Enclosure Design The frame end shields, terminal boxes and bearing covers of all motors are made of grey cast iron. The motors are so designed that the frame temperature will remain below the ignition temperature of the gas-air mixture involved. Insulation All motors of standard design are provided with Class F insulation with temperature rise limited to Class `B'. All cast iron parts forming the flame proof enclosures are subject to hydraulic pressure test, after final machining as per IS : 2148 Cooling All motors have bi-directional cast iron or fabricated fans. Terminal Box Location : flame proof motors have terminal box on the top as standard. Side terminal box can be offered on request for frame sizes 132M & above. Cable Entries Motors for mining application (Gas Group I ) are provided with cable entries with compound filling sealing boxes suitable for paper insulated lead covered double wired armoured (PILCDWA) PVC cables. Cable entries with flameproof cable glands can also be provided to suit PVC armoured cables. (for application in hazardous area Gas groups IIA & IIB only.) Motors in all frame sizes can be supplied with termination suitable for plug & socket arrangement, against enquiry. A cable sealing box is mandatory for all motors for use for Gas Group. 1 & Oil Mines. Ratings
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